U.S. patent application number 17/308273 was filed with the patent office on 2022-05-05 for multilayer electronic component.
The applicant listed for this patent is SAMSUNG ELECTRO-MECHANICS CO., LTD.. Invention is credited to Ji Hye Han, Byung Woo Kang, Jeong Ryeol Kim, Jung Min Kim, Bon Seok Koo, Hye Jin Park, Jae Seok Yi.
Application Number | 20220139618 17/308273 |
Document ID | / |
Family ID | 1000005613154 |
Filed Date | 2022-05-05 |
United States Patent
Application |
20220139618 |
Kind Code |
A1 |
Kang; Byung Woo ; et
al. |
May 5, 2022 |
MULTILAYER ELECTRONIC COMPONENT
Abstract
A multilayer electronic component includes a body including
first and second surfaces opposing each other in a first direction,
third and fourth surfaces connected to the first and second
surfaces and opposing each other in a second direction, and fifth
and sixth surfaces connected to the first to fourth surfaces and
opposing each other in a third direction and including a dielectric
layer and internal electrodes alternately disposed with the
dielectric layer interposed therebetween in the first direction,
and external electrodes disposed on the third and fourth surfaces,
wherein the external electrodes include an electrode layer disposed
on the body and a conductive resin layer disposed on the electrode
layer, and the conductive resin layer includes a conductive metal,
an epoxy resin, and an acrylic resin.
Inventors: |
Kang; Byung Woo; (Suwon-si,
KR) ; Koo; Bon Seok; (Suwon-si, KR) ; Kim;
Jeong Ryeol; (Suwon-si, KR) ; Kim; Jung Min;
(Suwon-si, KR) ; Yi; Jae Seok; (Suwon-si, KR)
; Han; Ji Hye; (Suwon-si, KR) ; Park; Hye Jin;
(Suwon-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAMSUNG ELECTRO-MECHANICS CO., LTD. |
Suwon-si |
|
KR |
|
|
Family ID: |
1000005613154 |
Appl. No.: |
17/308273 |
Filed: |
May 5, 2021 |
Current U.S.
Class: |
361/273 |
Current CPC
Class: |
H01G 4/015 20130101;
H01G 4/30 20130101; H01G 4/248 20130101 |
International
Class: |
H01G 4/015 20060101
H01G004/015; H01G 4/30 20060101 H01G004/30; H01G 4/248 20060101
H01G004/248 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 3, 2020 |
KR |
10-2020-0145462 |
Claims
1. A multilayer electronic component comprising: a body including
first and second surfaces opposing each other in a first direction,
third and fourth surfaces connected to the first and second
surfaces and opposing each other in a second direction, and fifth
and sixth surfaces connected to the first to fourth surfaces and
opposing each other in a third direction and including a dielectric
layer and internal electrodes alternately disposed with the
dielectric layer interposed therebetween in the first direction;
and external electrodes disposed on the third and fourth surfaces,
wherein the external electrodes include an electrode layer disposed
on the body and a conductive resin layer disposed on the electrode
layer, and the conductive resin layer includes a conductive metal,
an epoxy resin, and an acrylic resin.
2. The multilayer electronic component of claim 1, wherein the
external electrodes include connection portions disposed on the
third surface and the fourth surface and band portions extending
from the connection portions to the first and second surfaces, and
an average thickness of the conductive resin layer at the
connection portion is smaller than an average thickness of the
conductive resin layer at the band portion.
3. The multilayer electronic component of claim 2, wherein an
average thickness of the conductive resin layer at the connection
portion is less than 13 .mu.m.
4. The multilayer electronic component of claim 3, wherein an
average thickness of the conductive resin layer at the connection
portion is 7.4 .mu.m or less.
5. The multilayer electronic component of claim 4, wherein an
average thickness of the conductive resin layer at the band portion
exceeds 9.43 .mu.m.
6. The multilayer electronic component of claim 2, wherein an
average thickness of the conductive resin layer at the band portion
exceeds 9.43 .mu.m.
7. The multilayer electronic component of claim 6, wherein an
average thickness of the conductive resin layer at the connection
portion is less than 13 .mu.m.
8. The multilayer electronic component of claim 2, wherein the
conductive resin layer is disposed to cover at least a portion of
the electrode layer at the band portion.
9. The multilayer electronic component of claim 8, wherein the
conductive resin layer is disposed to cover the entirety of the
electrode layer.
10. The multilayer electronic component of claim 2, wherein the
external electrode includes a plating layer disposed on the
conductive resin layer.
11. The multilayer electronic component of claim 1, wherein the
external electrodes include connection portions disposed on the
third and fourth surfaces and band portions extending from the
connection portions to the first and second surfaces, the electrode
layer is disposed at the connection portion and the band portion,
and the conductive resin layer is disposed on the electrode layer
of the band portion.
12. The multilayer electronic component of claim 11, wherein the
conductive resin layer extends to at least a portion of the
electrode layer of the connection portion.
13. The multilayer electronic component of claim 11, wherein the
conductive resin layer is not disposed on the electrode layer of
the connection portion.
14. The multilayer electronic component of claim 11, wherein the
external electrode includes a plating layer, at least a portion of
the plating layer is in direct contact with the electrode layer at
the connection portion, and the plating layer is in direct contact
with the conductive resin layer at the band portion.
15. The multilayer electronic component of claim 11, wherein the
conductive resin layer is discontinuously disposed on the electrode
layer at the connection portion.
16. The multilayer electronic component of claim 1, wherein the
electrode layer includes a conductive metal and glass.
17. A multilayer electronic component comprising: a body including
first and second surfaces opposing each other in a first direction,
third and fourth surfaces connected to the first and second
surfaces and opposing each other in a second direction, and fifth
and sixth surfaces connected to the first to fourth surfaces and
opposing each other in a third direction and including a dielectric
layer and internal electrodes alternately disposed with the
dielectric layer interposed therebetween in the first direction;
and external electrodes disposed on the third and fourth surfaces,
wherein the external electrodes include an electrode layer disposed
on the body and a conductive resin layer disposed on the electrode
layer, the external electrodes include connection portions disposed
on the third surface and the fourth surface and band portions
extending from the connection portions to the first and second
surfaces, the conductive resin layer includes a conductive metal,
and an epoxy resin, an average thickness of the conductive resin
layer at the connection portion is less than 13 .mu.m, and an
average thickness of the conductive resin layer at the band portion
exceeds 9.43 .mu.m.
18. The multilayer electronic component of claim 17, wherein an
average thickness of the conductive resin layer at the connection
portion is smaller than an average thickness of the conductive
resin layer at the band portion.
19. The multilayer electronic component of claim 17, wherein an
average thickness of the conductive resin layer at the connection
portion is 7.4 .mu.m or less.
20. The multilayer electronic component of claim 17, wherein an
average thickness of the conductive resin layer at the band portion
is 15.21 .mu.m or more.
21. The multilayer electronic component of claim 18, wherein the
conductive resin layer is disposed on the electrode layer of the
band portion and extends to at least a portion of the electrode
layer of the connection portion.
22. The multilayer electronic component of claim 18, wherein the
external electrode includes a plating layer disposed on the
conductive resin layer.
23. The multilayer electronic component of claim 17, wherein the
electrode layer is disposed at the connection portion and the band
portion, and the conductive resin layer is disposed on the
electrode layer of the band portion.
24. The multilayer electronic component of claim 17, wherein the
external electrode includes a plating layer, at least a portion of
the plating layer is in direct contact with the electrode layer at
the connection portion, and the plating layer is in direct contact
with the conductive resin layer at the band portion.
25. The multilayer electronic component of claim 17, wherein the
electrode layer includes a conductive metal and glass.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims benefit of priority to Korean Patent
Application No. 10-2020-0145462 filed on Nov. 3, 2020 in the Korean
Intellectual Property Office, the disclosure of which is
incorporated herein by reference in its entirety.
BACKGROUND
1. Field
[0002] The present disclosure relates to a multilayer electronic
component.
2. Description of Related Art
[0003] A multilayer ceramic capacitor (MLCC), a multilayer
electronic component, is a chip-type condenser mounted on printed
circuit boards of various types of electronic products such as
display devices including liquid crystal displays (LCDs) and plasma
display panels (PDPs), computers, smartphones, cell phones, and the
like to allow electricity to be charged therein and discharged
therefrom.
[0004] Such an MLCC having advantages such as compactness,
guaranteed high capacitance, and ease in mounting thereof may be
used as a component of various electronic devices. As various
electronic devices such as computers, mobile devices, and the like,
have become smaller and higher in terms of power output, demand for
miniaturization and higher capacity of multilayer ceramic
capacitors has increased.
[0005] In addition, as industry interest in electric parts for
automobiles has recently increased, MLCCs are also required to have
high reliability and high strength characteristics in order to be
used in automobile or infotainment systems.
[0006] In order to ensure high reliability and high strength
characteristics, a method of modifying external electrodes formed
of electrode layers to have a dual-layer structure including an
electrode layer and a conductive resin layer has been proposed.
[0007] The dual-layer structure of the electrode layer and the
conductive resin layer may absorb external impacts by applying a
resin composition containing a conductive material to the electrode
layer and improve reliability by preventing penetration of a
plating solution.
[0008] However, as the standards for high reliability and high
strength characteristics required in the industry are gradually
being increased, a method for further improving high reliability
and high strength characteristics in line therewith is
required.
SUMMARY
[0009] Exemplary embodiments provide a multilayer electronic
component having improved flexural strength characteristics
generated in the multilayer electronic component.
[0010] Exemplary embodiments provide a multilayer electronic
component having a low equivalent series resistance (ESR).
[0011] However, the aspect of the present disclosure is not limited
to the aforementioned contents and may be more easily understood in
the process of describing a specific exemplary embodiment in the
present disclosure.
[0012] According to an exemplary embodiment, a multilayer
electronic component includes: a body including first and second
surfaces opposing each other in a first direction, third and fourth
surfaces connected to the first and second surfaces and opposing
each other in a second direction, and fifth and sixth surfaces
connected to the first to fourth surfaces and opposing each other
in a third direction and including a dielectric layer and internal
electrodes alternately disposed with the dielectric layer
interposed therebetween in the first direction; and external
electrodes disposed on the third and fourth surfaces, wherein the
external electrodes include an electrode layer disposed on the body
and a conductive resin layer disposed on the electrode layer, and
the conductive resin layer includes a conductive metal, an epoxy
resin, and an acrylic resin.
BRIEF DESCRIPTION OF DRAWINGS
[0013] The above and other aspects, features, and advantages of the
present disclosure will be more clearly understood from the
following detailed description, taken in conjunction with the
accompanying drawings, in which:
[0014] FIG. 1 is a schematic perspective view of a multilayer
electronic component according to an exemplary embodiment in the
present disclosure;
[0015] FIG. 2 is a cross-sectional view taken along line I-I' of
FIG. 1;
[0016] FIG. 3 is an exploded perspective view schematically
illustrating a body in which a dielectric layer and an internal
electrode are laminated according to an exemplary embodiment in the
present disclosure.
[0017] FIG. 4 is an enlarged view of region K1 of FIG. 2;
[0018] FIG. 5 is an enlarged view of region K2 of FIG. 2;
[0019] FIG. 6 is a view illustrating a bending test method;
[0020] FIG. 7 is a graph evaluating flexural strength of a
multilayer electronic component according to whether a conductive
resin layer of the present disclosure is applied, showing a bending
test result according to the test method of FIG. 5;
[0021] FIG. 8 is a cross-sectional view of a multilayer electronic
component according to another exemplary embodiment in the present
disclosure corresponding to FIG. 2; and
[0022] FIG. 9 is a cross-sectional view of a multilayer electronic
component according to another exemplary embodiment in the present
disclosure corresponding to FIG. 2.
DETAILED DESCRIPTION
[0023] The following detailed description is provided to assist the
reader in gaining a comprehensive understanding of the methods,
apparatuses, and/or systems described herein. However, various
changes, modifications, and equivalents of the methods,
apparatuses, and/or systems described herein will be apparent to
one of ordinary skill in the art. The sequences of operations
described herein are merely examples, and are not limited to those
set forth herein, but may be changed as will be apparent to one of
ordinary skill in the art, with the exception of operations
necessarily occurring in a certain order. Also, descriptions of
functions and constructions that would be well known to one of
ordinary skill in the art may be omitted for increased clarity and
conciseness.
[0024] The features described herein may be embodied in different
forms, and are not to be construed as being limited to the examples
described herein. Rather, the examples described herein have been
provided so that this disclosure will be thorough and complete, and
will fully convey the scope of the disclosure to one of ordinary
skill in the art.
[0025] Herein, it is noted that use of the term "may" with respect
to an example or embodiment, e.g., as to what an example or
embodiment may include or implement, means that at least an example
or embodiment exists in which such a feature is included or
implemented while all examples and embodiments are not limited
thereto.
[0026] Throughout the specification, when an element, such as a
layer, region, or substrate, is described as being "on," "connected
to," or "coupled to" another element, it may be directly "on,"
"connected to," or "coupled to" the other element, or there may be
one or more other elements intervening therebetween. In contrast,
when an element is described as being "directly on," "directly
connected to," or "directly coupled to" another element, there can
be no other elements intervening therebetween.
[0027] As used herein, the term "and/or" includes any one and any
combination of any two or more of the associated listed items.
[0028] Although terms such as "first," "second," and "third" may be
used herein to describe various members, components, regions,
layers, or sections, these members, components, regions, layers, or
sections are not to be limited by these terms. Rather, these terms
are only used to distinguish one member, component, region, layer,
or section from another member, component, region, layer, or
section. Thus, a first member, component, region, layer, or section
referred to in examples described herein may also be referred to as
a second member, component, region, layer, or section without
departing from the teachings of the examples.
[0029] Spatially relative terms such as "above," "upper," "below,"
and "lower" may be used herein for ease of description to describe
one element's relationship to another element as illustrated in the
figures. Such spatially relative terms are intended to encompass
different orientations of the device in use or operation in
addition to the orientation depicted in the figures. For example,
if the device in the figures is turned over, an element described
as being "above" or "upper" relative to another element will then
be "below" or "lower" relative to the other element. Thus, the term
"above" encompasses both the above and below orientations depending
on the spatial orientation of the device. The device may also be
oriented in other ways (for example, rotated 90 degrees or at other
orientations), and the spatially relative terms used herein are to
be interpreted accordingly.
[0030] The terminology used herein is for describing various
examples only, and is not to be used to limit the disclosure. The
articles "a," "an," and "the" are intended to include the plural
forms as well, unless the context clearly indicates otherwise. The
terms "comprises," "includes," and "has" specify the presence of
stated features, numbers, operations, members, elements, and/or
combinations thereof, but do not preclude the presence or addition
of one or more other features, numbers, operations, members,
elements, and/or combinations thereof.
[0031] Due to manufacturing techniques and/or tolerances,
variations of the shapes illustrated in the drawings may occur.
Thus, the examples described herein are not limited to the specific
shapes illustrated in the drawings, and may include changes in
shape occurring during manufacturing.
[0032] The features of the examples described herein may be
combined in various manners, as will be apparent after gaining an
understanding of the disclosure of this application. Further,
although the examples described herein have a variety of
configurations, other configurations are possible, as will be
apparent after an understanding of the disclosure of this
application.
[0033] The drawings may not be to scale, and the relative size,
proportions, and depiction of elements in the drawings may be
exaggerated for clarity, illustration, and convenience. In the
drawing, X direction may be defined as a second direction or a
length direction of a body, Y direction may be defined as a third
direction or a width direction of the body, and Z direction may be
defined as a first direction or a thickness direction or a
lamination direction of the body.
[0034] Multilayer Electronic Component
[0035] FIG. 1 is a schematic perspective view of a multilayer
electronic component according to an exemplary embodiment in the
present disclosure.
[0036] FIG. 2 is a cross-sectional view taken along line I-I' of
FIG. 1.
[0037] FIG. 3 is an exploded perspective view schematically
illustrating a body in which a dielectric layer and an internal
electrode are laminated according to an exemplary embodiment in the
present disclosure.
[0038] FIG. 4 is an enlarged view of region K1 of FIG. 2.
[0039] FIG. 5 is an enlarged view of region K2 of FIG. 2.
[0040] Hereinafter, a multilayer electronic component 100 according
to an exemplary embodiment in the present disclosure will be
described with reference to FIGS. 1 through 5.
[0041] The multilayer electronic component 100 according to an
exemplary embodiment in the present disclosure includes a body 110
including first and second surfaces 1 and 2 opposing each other in
the first direction (Z direction), third and fourth surfaces 3 and
4 connected to the first and second surfaces 1 and 2 and opposing
each other in the second direction (X direction), and fifth and
sixth surfaces 5 and 6 connected to the first to fourth surfaces
and opposing each other in the third direction (Y direction) and
including a dielectric layer 111 and internal electrodes 121 and
122 alternately disposed with the dielectric layer interposed
therebetween in the first direction; and external electrodes 131
and 132 disposed on the third and fourth surfaces, wherein the
external electrodes 131 and 132 include electrode layers 131a and
132a disposed on the body and conductive resin layers 131b and 132b
disposed on the electrode layers 131a and 132a, and the conductive
resin layers include a conductive metal, an epoxy resin, and an
acrylic resin.
[0042] In the body 110, the dielectric layer 111 and the internal
electrodes 121 and 122 are alternately laminated.
[0043] The body 110 may be formed in a hexahedral shape or a
similar shape, but there is no limitation on a specific shape.
[0044] A specific shape of the body 110 is not limited, but, as
illustrated, the body 110 may have a hexahedral shape or a similar
shape. Due to shrinkage of ceramic powder particle contained in the
body 110 during firing, the body 110 may not have a hexahedral
shape with perfect straight lines but a substantially hexahedral
shape.
[0045] The body 110 may have the first and second surfaces 1 and 2
opposing each other in the first direction (Z direction), the third
and fourth surfaces 3 and 4 connected to the first and second
surfaces 1 and 2 and opposing each other in the second direction (X
direction), and the fifth and sixth surfaces 5 an 6 connected to
the first and second surfaces 1 and 2, connected to the third and
fourth surfaces 3 and 4, and opposing each other in the third
direction (Y direction).
[0046] A plurality of dielectric layers 111 forming the body 110
are in a sintered state, and adjacent dielectric layers 111 may be
integrated such that boundaries therebetween may not be readily
apparent without using a scanning electron microscope (SEM).
[0047] According to an exemplary embodiment in the present
disclosure, a material for forming the dielectric layer 111 is not
limited as long as sufficient electrostatic capacity may be
obtained. For example, a barium titanate-based material, a lead
composite perovskite-based material, or a strontium titanate-based
material may be used. The barium titanate-based material may
include a BaTiO.sub.3-based ceramic powder particle, and the
ceramic powder particle may include BaTiO.sub.3 and
(Ba.sub.1-xCa.sub.x) TiO.sub.3 (0<x<1),
Ba(Ti.sub.1-yCa.sub.y) O.sub.3 (0<y<1), (Ba.sub.1-xCa.sub.x)
(Ti.sub.1-yZr.sub.y) O.sub.3 (0<x<1 and 0<y<1), or
Ba(Ti.sub.1-yZr.sub.y)O.sub.3 (0<y<1) obtained by partially
dissolving calcium (Ca), zirconium (Zr), and the like in
BaTiO.sub.3.
[0048] As a material for forming the dielectric layer 111, various
ceramic additives, organic solvents, binders, dispersants, etc. may
be added to the powder particle such as barium titanate
(BaTiO.sub.3) or the like according to purposes of the present
disclosure.
[0049] The body 110 may include a capacitance forming portion
formed inside the body 110 and forming capacitance with the first
internal electrode 121 and the second internal electrode 122
disposed to face each other with the dielectric layer 111
interposed therebetween and protective layers 112 and 113 formed
above and below the capacitance forming portion.
[0050] The capacitance forming portion is a part that contributes
to formation of capacitance of the capacitor, which may be formed
by repeatedly laminating a plurality of first and second internal
electrodes 121 and 122 with the dielectric layer 111 interposed
therebetween.
[0051] The upper protective layer 112 and the lower protective
layer 113 may be formed by laminating a single dielectric layer or
two or more dielectric layers on upper and lower surfaces of the
capacitance forming portion in an up-down direction, respectively,
and may basically serve to prevent damage to the internal
electrodes due to physical or chemical stress.
[0052] The upper protective layer 112 and the lower protective
layer 113 may not include an internal electrode and may include the
same material as that of the dielectric layer 111.
[0053] The internal electrodes 121 and 122 may be disposed to face
each other with the dielectric layer 111 interposed
therebetween.
[0054] The internal electrodes may include first and second
internal electrodes 121 and 122 alternately disposed to face each
other with the dielectric layer interposed therebetween.
[0055] The first and second internal electrodes 121 and 122 may be
exposed to the third and fourth surfaces 3 and 4 of the body 110,
respectively.
[0056] Referring to FIG. 2, the first internal electrode 121 may be
spaced apart from the fourth surface 4 and exposed to the third
surface 3, and the second internal electrode 122 may be spaced
apart from the third surface 3 and exposed to the fourth surface 4.
The first external electrode 131 may be disposed on the third
surface 3 of the body and connected to the first internal electrode
121, and the second external electrode 132 may be disposed on the
fourth surface 4 of the body and connected to the second internal
electrode 122.
[0057] In other words, the first internal electrode 121 may not be
connected to the second external electrode 132 and may be connected
to the first external electrode 131, and the second internal
electrode 122 may not be connected to the first external electrode
131 and may be connected to the second external electrode 132.
Accordingly, the first internal electrode 121 is formed to be
spaced apart from the fourth surface 4 by a predetermined distance,
and the second internal electrode 122 is formed to be spaced apart
from the third surface 3 by a predetermined distance.
[0058] The first and second internal electrodes 121 and 122 may be
electrically separated from each other by the dielectric layer 111
disposed therebetween.
[0059] Referring to FIG. 3, the body 110 may be formed by
laminating the dielectric layer 111 on which the first internal
electrode 121 is printed and the dielectric layer 111 on which the
second internal electrode 122 is printed in the thickness direction
(Z direction) and subsequently firing the laminate.
[0060] A material forming the internal electrodes 121 and 122 is
not limited, and a material having excellent electrical
conductivity may be used. For example, the internal electrodes 121
and 122 may be formed by printing a conductive paste for internal
electrodes including at least one of nickel (Ni), copper (Cu),
palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn),
tungsten (W), titanium (Ti), or alloys thereof on a ceramic green
sheet.
[0061] As a printing method of the conductive paste for internal
electrodes, a screen printing method or a gravure printing method
may be used and the present disclosure is not limited thereto.
[0062] The first and second external electrodes 131 and 132 are
disposed on the body 110 and include electrode layers 131a and 132a
and conductive resin layers 131b and 132b, respectively.
[0063] The external electrodes may include first and second
external electrodes 131 and 132 connected to the first and second
internal electrodes 121 and 122, respectively.
[0064] The first external electrode 131 may include a first
electrode layer 131a and a first conductive resin layer 131b, and
the second external electrode 132 may include a second electrode
layer 132a and a second conductive resin layer 132b.
[0065] The first and second electrode layers 131 and 132 may be
formed of any material as long as the material has electrical
conductivity, such as a metal, and a specific material may be
determined in consideration of electrical characteristics and
structural stability.
[0066] For example, the first and second electrode layers 131 and
132 may include a conductive metal and glass.
[0067] A conductive metal used in the electrode layers 131a and
132a is not limited as long as it is a material that can be
electrically connected to the internal electrode for forming
capacitance. For example, the conductive metal may include at least
one selected from the group consisting of nickel (Ni), copper (Cu),
palladium (Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn),
tungsten (W), titanium (Ti), and alloys thereof.
[0068] The electrode layers 131a and 132a may be formed by applying
a conductive paste prepared by adding a glass frit to the
conductive metal powder particle and subsequently firing the
conductive paste.
[0069] In addition, the first and second electrode layers 131a and
132a may also be formed using an atomic layer deposition (ALD), a
molecular layer deposition (MLD) method, a chemical vapor
deposition (CVD) method, a sputtering method, or the like.
[0070] In addition, the first and second electrode layers 131a and
132a may be formed by transferring a sheet including a conductive
metal to the body 110.
[0071] The conductive resin layers 131b and 132b may include a
conductive metal, and an epoxy resin. Also, the conductive resin
layers 131b and 132b include a conductive metal, an epoxy resin,
and an acrylic resin.
[0072] The conductive metal included in the conductive resin layers
131b and 132b serves to electrically connect the conductive resin
layers 131b and 132b to the electrode layers 131a and 132a,
respectively.
[0073] The conductive metal included in the conductive resin layers
131b and 132b is not particularly limited as long as it is a
material that can be electrically connected to the electrode layers
131a and 132a, and may include at least one selected from the group
consisting of, for example, nickel (Ni), copper (Cu), palladium
(Pd), silver (Ag), gold (Au), platinum (Pt), tin (Sn), tungsten
(W), titanium (Ti), and alloys thereof.
[0074] The conductive metal included in the conductive resin layers
131b and 132b may include at least one of a spherical powder
particle or a flake powder particle. That is, the conductive metal
may be formed of only the flake particle or only the spherical
particle or may be formed of a mixture of the flake particle and
the spherical particle.
[0075] Here, the spherical particle may include a form that is not
completely spherical, for example, a form in which a length ratio
of a major axis and a minor axis (major axis/minor axis) is 1.45 or
less.
[0076] The flake particle refers to a particle having a flat and
elongated shape, in which a length ratio of a major axis and a
minor axis (major axis/minor axis) may be 1.95 or more, but is not
limited thereto.
[0077] The lengths of the major axis and the minor axis of the
spherical powder particle and the flake particle may be measured
from an image obtained by scanning an X and Z-directional
cross-section (L-T cross-section) taken at a central portion of a
multilayer electronic component in the width direction Y with the
SEM.
[0078] The epoxy resin and acrylic resin included in the conductive
resin layers 131b and 132b serve to ensure bondability and absorb
impacts.
[0079] In general, in the related art, an epoxy resin was used as a
resin included in the conductive resin layer. However, there is a
limit to increasing ductility with only the epoxy resin.
[0080] Thus, according to an exemplary embodiment in the present
disclosure, ductility of the conductive resin layers 131b and 132b
is maximized by adding both the epoxy resin and the acrylic resin
to the conductive resin layers 131b and 132b, thereby improving
flexural strength characteristics. When both the epoxy resin and
the acrylic resin are added, superior mechanical properties as
compared with a case in which the epoxy resin or acrylic resin is
added alone may be secured, thereby improving the flexural strength
characteristics.
[0081] The epoxy resin and the acrylic resin included in the
conductive resin layers 131b and 132b may be determined through
secondary ion mass spectrometry (SIMS) analysis. Here, the SIMS
analysis refers to an analysis method of causing primary ions
(Bi.sup.nm+, O.sup.2+, Cs.sup.+, Ar.sup.n+) with appropriate keV
energy to collide with a surface of a material and analyzing a mass
of ionized particles emitted from the surface of the sample to
thereby obtain information on atoms present on the surface and a
structural arrangement thereof.
[0082] FIG. 6 is a view illustrating a bending test method.
[0083] FIG. 7 is a graph evaluating flexural strength of a
multilayer electronic component in which a conductive resin layer
of the present disclosure is applied, showing a bending test result
according to the test method of FIG. 5.
[0084] In FIG. 7, a conductive resin layer of Comparative Example
includes a conductive metal and an epoxy resin but does not include
an acrylic resin, and the conductive resin layers of Inventive
Examples 1 and 2 include a conductive metal, an epoxy resin, and an
acrylic resin. In addition, Comparative Example and Inventive
Example 1 have an external electrode structure in which a
conductive resin layer is disposed even at a connection portion as
shown in FIG. 2, and Inventive Example 2 has an external electrode
structure in which a conductive resin layer is not disposed in a
partial region of a connection portion as shown in FIG. 8. Thirty
samples were prepared for each of Comparative Example, Inventive
Example 1, and Inventive Example 2.
[0085] Referring to FIG. 6, a sample chip (MLCC) was mounted on a
printed circuit board (PCB), and a side opposite to a side on which
the sample chip (MLCC) was mounted was pressed by up to 6 mm,
during which a point where the external electrode was separated
from the body to end up with peel-off or a point where the body was
cracked to end up with cracking was indicated as piezo peak
position in FIG. 6.
[0086] In Comparative Example, the body was cracked in 19 out of 30
samples. Meanwhile, in the case of Inventive Examples 1 and 2, none
of the 30 samples had peel-off or cracking. Therefore, it was
confirmed that flexural strength may be guaranteed in the 6 mm
flexural strength test when the conductive resin layer includes
both the epoxy resin and the acrylic resin.
[0087] Here, a ratio of the epoxy resin and the acrylic resin of
the conductive resin layer does not need to be particularly limited
and may be appropriately determined in consideration of a length, a
thickness, and the like, of a band portion of the conductive resin
layer and in consideration of tensile strength, elongation, Young's
modulus, and the like based on the ratio of the epoxy resin and the
acrylic resin. For example, when the sum of weight of the epoxy
resin and the acrylic resin of the conductive resin layer is 100, a
weight ratio of the epoxy resin to the acrylic resin may be 25 to
75%: 75 to 25%. That is, when the sum of the epoxy resin and the
acrylic resin in the conductive resin layer is 100 wt %, the epoxy
resin may be 25 wt % to 75 wt % and the remainder may be the
acrylic resin.
[0088] In addition, in the conductive resin layer, the weight
content of the sum of the epoxy resin and the acrylic resin
relative to the conductive metal need not be particularly limited.
That is, the content may be appropriately determined in
consideration of an electrical characteristic and flexural strength
characteristics. For example, the weight content of the sum of the
epoxy resin and the acrylic resin relative to the conductive metal
may be 2% or more and 25% or less.
[0089] Meanwhile, the epoxy resin and the acrylic resin included in
the conductive resin layer may not need to be limited in type.
[0090] For example, the epoxy resin may include bisphenol-A
(BPA)-based epoxy, novolac-based epoxy, and the like, and the
acrylic resin may include an acrylate-based resin, a
methacrylate-based resin, and the like.
[0091] The external electrodes 131 and 132 may include connection
portions A1 and A2 disposed on the third and fourth surfaces of the
body 110, respectively, and band portions B1 and B2 extending from
the connection portions to the first and second surfaces,
respectively.
[0092] Referring to FIG. 2, when regions of the first external
electrode 131 are divided according to positions, the first
external electrode 131 may include a first connection portion A1
disposed on the third surface 3 of the body and a first band
portion B1 extending from the first connection portion A1 to parts
of the first, second, fifth, and sixth surfaces 1, 2, 5, and 6 of
the body.
[0093] When regions of the second external electrode 132 are
divided according to positions, the second external electrode 132
may include a second connection portion A2 disposed on the fourth
surface 4 of the body and a second band portion B2 extending from
the second connection portion A2 to parts of the first, second,
fifth, and sixth surfaces 1, 2, 5, and 6 of the body.
[0094] Referring to FIG. 2, as only one of the first and second
internal electrodes 121 and 122 is disposed at the end of the body
110 in the length direction (X direction), a step may occur.
Accordingly, the edge of the body 110 in the length direction (X
direction) may have a thickness smaller than that of a central
portion of the body 110 in the length direction (X direction), and
the first and second surfaces 1 and 2 may be shrunken to the
central portion of the body 110 in the thickness direction (Z
direction) at the end of the body 110 in the length direction (X
direction).
[0095] According to an exemplary embodiment in the present
disclosure, an average thickness of the conductive resin layers
131b and 132b at the connection portions A1 and A2, respective, may
be smaller than an average thickness thereof at the band portions
B1 and B2, respectively. A thickness of the conductive resin layers
at the connection portions is a thickness that is perpendicular the
surface 3 or 4 of the body. A thickness of the conductive resin
layers at the connection portions is a thickness that is
perpendicular the surface 1, 2, 5 or 6 of the body. Referring to
FIG. 2, the average thickness of the band portions in Table 1 is a
value obtained by averaging maximum values of the conductive resin
layers 131b and 132b at four band portions of the external
electrodes disposed on the first surface and the second surface of
the body in the cross-section (L-T cross-section) taken in the
length direction (X direction) and thickness direction (Z
direction) at the center of the body in the width direction
(Y-direction).
[0096] In the case of adding both the epoxy resin and the acrylic
resin to the conductive resin layers 131b and 132b to maximize
ductility of the conductive resin layers 131b and 132b, an
equivalent series resistance (ESR) characteristic may increase.
[0097] According to an exemplary embodiment in the present
disclosure, the average thickness of the conductive resin layers
131b and 132b is large at the band portions B1 and B2 that
significantly affect the flexural strength characteristics, and the
average thickness of the conductive resin layers 131b and 132b is
small at the connection portions A1 and A2 that significantly
affect ESR, thereby lowering the ESR, while ensuring the flexural
strength characteristics.
[0098] A manufacturing method for implementing a structure in which
the average thickness of the conductive resin layers 131b and 132b
at the connection portions A1 and A2 is small is not particularly
limited.
[0099] For example, a method of forming the electrode layers 131a
and 132a on the body 110, applying a paste for a conductive resin
layer to the electrode layers 131a and 132a, removing the paste for
a conductive resin layer applied to the connection portion using a
porous nonwoven fabric, and performing a curing process to form the
conductive resin layers 131b and 132b may be used.
[0100] Here, the average thickness of the conductive resin layers
131b and 132b in the connection portions A1 and A2 may be less than
13 .mu.m.
[0101] If the average thickness of the conductive resin layers 131b
and 132b at the connection portions A1 and A2 is 13 .mu.m or more,
the ESR may increase to deteriorate electrical characteristics.
Therefore, the average thickness of the conductive resin layers
131b and 132b at the connection portions A1 and A2 is preferably
less than 13 .mu.m, and, more preferably, 7.4 .mu.m or less.
[0102] Table 1 below shows evaluation of the ESR and flexural
strength characteristics according to the average thicknesses of
the conductive resin layers 131b and 132b at the connection
portions A1 and A2 and the band portions B1 and B2.
[0103] Referring to FIG. 5, the thicknesses of the conductive resin
layer 131b at respective positions of the connection portion of
Table 1 were measured from five points P1, P2, P3, P4, and P5 at
equal intervals from the lowermost internal electrode 121 to the
uppermost internal electrode 121 in a cross-section (L-T
cross-section) taken in the length direction (X direction) and
thickness direction (Z direction) at the center of the body in the
width direction (Y-direction), and the average thickness of the
connection portion in Table 1 is an average value of the
thicknesses of the conductive resin layer 131b at the 5 points P1,
P2, P3, P4, and P5.
[0104] Referring to FIG. 2, the average thickness of the band
portions in Table 1 is a value obtained by averaging maximum values
of the conductive resin layers 131b and 132b at four band portions
of the external electrodes disposed on the first surface and the
second surface of the body in the cross-section (L-T cross-section)
taken in the length direction (X direction) and thickness direction
(Z direction) at the center of the body in the width direction
(Y-direction).
[0105] Referring to FIG. 6, thirty sample chips per test No. were
prepared and each sample chip (MLCC) was mounted on a PCB. It was
determined whether peel-off occurred as the external electrode is
separated from the body or whether cracking occurred as the body
cracked, while pressing the opposite surface of the surface on
which the sample chip (MLCC) is mounted. A case in which the number
of samples in which peel-off or cracking occurred was five or less
is marked as "O," while a case in which the number of samples in
which peel-off or cracking occurred exceeded five is marked as
"X."
[0106] Each measurement value of ESR is shown in Table 1 below, in
which ESR of 200 m.OMEGA. or less is marked as O and ESR exceeding
200 m.OMEGA. is marked as X.
TABLE-US-00001 TABLE 1 Average thickness Average Thickness of
connection of thickness portion at each connection of band Test
position (.mu.m) portion portion ESR Flexural No. P1 P2 P3 P4 P5
(.mu.m) (.mu.m) (m.OMEGA.) strength 1 13.9 45.6 61.9 38.3 9.9 33.9
24.25 139548 X .largecircle. 2 13.9 45.6 61.9 38.3 9.9 33.9 17.45
139548 X .largecircle. 3 13.9 45.6 61.9 38.3 9.9 33.9 9.11 139548 X
X 4 12.1 30.3 49.8 29.4 11.5 26.6 24.25 133406 X .largecircle. 5
9.5 16.1 26.6 16.9 8.9 15.6 20.04 31385 X .largecircle. 6 9.5 16.1
26.6 16.9 8.9 15.6 9.15 31385 X X 7 8.3 15.4 24.1 11.4 5.8 13.0
17.99 319 X .largecircle. 8 8.3 15.4 24.1 11.4 5.8 13.0 9.43 319 X
X 9 4.1 7.7 11.9 8.2 4.9 7.4 16.85 20.1 .largecircle. .largecircle.
10 3.4 6.1 8.9 6.4 3.1 5.6 20.04 18.7 .largecircle. .largecircle.
11 2.2 3.5 5.5 3.6 2.4 3.4 26.50 16.4 .largecircle. .largecircle.
12 2.1 1.4 0.4 1.1 1.6 1.3 15.21 13.9 .largecircle.
.largecircle.
[0107] Referring to Table 1, test Nos. 3, 6, and 8 in which the
average thickness of the band portions is small although the
average thickness of the conductive resin layers 131b and 132b at
the connection portions A1 and A2 is large are evaluated to have
low flexural strength, confirming that the influence of the average
thickness of the conductive resin layers 131b and 132b at the
connection portions A1 and A2 on the flexural strength is
limited.
[0108] In addition, it can be seen that, in the case of Test Nos. 1
to 8 in which the average thickness of the conductive resin layers
131b and 132b at the connection portions A1 and A2 is 13 .mu.m or
more, the ESR increases rapidly as the thickness increases.
[0109] Meanwhile, it can be seen that Test Nos. 9 to 12 in which
the average thickness of the conductive resin layers 131b and 132b
at the connection portions A1 and A2 is less than 13 .mu.m have
excellent flexural strength characteristics, while the ESR is
low.
[0110] Meanwhile, the average thickness of the conductive resin
layers 131b and 132b at the band portions B1 and B2 need not be
particularly limited. However, in order to ensure a sufficient
flexural strength characteristics, the average thickness of the
conductive resin layers 131b and 132b at the band portions B1 and
B2 may be greater than 9.43 .mu.m. More preferably, the average
thickness of the conductive resin layers 131b and 132b at the band
portions B1 and B2 may be 15.21 .mu.m or more.
[0111] Referring to Table 1, it can be seen that Test Nos, 3, 6 and
8 in which the average thickness of the conductive resin layers
131b and 132b at the band portions B1 and B2 is 9.43 .mu.m or less
have low flexural strength and Test Nos. 1, 2, 4, 5, 7, and 9 to 12
in which the average thickness of the conductive resin layers 131b
and 132b at the band portions B1 and B2 is greater than 9.43 .mu.m
have excellent flexural strength.
[0112] At the band portions B1 and B2, the conductive resin layers
131b and 132b may be disposed to cover at least a portion of the
electrode layers 131a and 132a. In addition, at the band portions
B1 and B2, the conductive resin layers 131b and 132b may be
disposed to cover the entirety of the electrode layers 131a and
132a. That is, referring to FIG. 4, a length B1b of the band
portion of the conductive resin layer may be greater than a length
B1a of the band portion of the electrode layer. Accordingly, the
flexural strength characteristics may be further improved, and
moisture resistance reliability may be improved by covering the
ends of the band portions of the electrode layers 131a and 132a to
block a moisture penetration path.
[0113] The external electrodes 131 and 132 may include plating
layers 131c and 132c disposed on the conductive resin layers 131b
and 132b.
[0114] The plating layers 131c and 132c may be plating layers
including at least one of nickel (Ni), tin (Sn), palladium (Pd),
and alloys thereof and may be formed of a plurality of layers.
[0115] For a more specific example of the plating layers 131c and
132c, the plating layers 131c and 132c may be Ni plating layers or
Sn plating layers, may include the Ni plating layer and the Sn
plating layer which are sequentially formed, or may include the Sn
plating layer, the Ni plating layer, and the Sn plating layer which
are sequentially formed. In addition, the plating layers 131c and
132c may include a plurality of Ni plating layers and/or a
plurality of Sn plating layers.
[0116] Meanwhile, referring to FIG. 8, in an exemplary embodiment
in the present disclosure, external electrodes 131' and 132'
include connection portions A1 and A2, respectively, disposed on
the third and fourth surfaces of the body 110, respectively, and
band portions B1 and B2 extending from the connection portions A1
and A2, respectively, and disposed on the first and second
surfaces, respectively. Electrode layers 131a' and 132a' may be
disposed on the connection portions A1 and A2, respectively, and
the band portions B1 and B2, respectively, and conductive resin
layers 131b' and 132b' may be disposed on the electrode layers
131a' and 132a' of the band portions B1 and B2, respectively.
[0117] According to an exemplary embodiment in the present
disclosure, at the band portions B1 and B2 that significantly
affect the flexural strength characteristics, the conductive resin
layers 131b' and 132b' are disposed on the electrode layers 131a'
and 132a', and at the connection portions A1 and A2 that
significantly affect ESR, the conductive resin layers 131b' and
132b' may not be disposed on the electrode layers 131a' and 132a',
respectively, or may be disposed only at a partial region thereof,
thereby lowering the ESR, while the flexural strength
characteristics is ensured.
[0118] Here, the conductive resin layers 131b' and 132b' may be
disposed on the electrode layers 131a' and 132a' of the band
portions B1 and B2, so that the conductive resin layers 131b' and
132b' may extend onto at least a portion of the electrode layers
131a' and 132a' of the connection portions A1 and A2.
[0119] If the electrode layers 131a' and 132a' include conductive
metal and glass, the electrode layers 131a' and 132a' may be formed
to have a small thickness at a region in which the connection
portions A1 and A2 and the band portions B1 and B2 meet. In this
case, the region in which the connection portions A1 and A2 and the
band portions B1 and B2 meet may be a main moisture penetration
path to degrade moisture resistance reliability.
[0120] According to an exemplary embodiment in the present
disclosure, since the conductive resin layers 131b' and 132b' are
disposed to extend from the band portions B1 and B2 to a part of
the connection portions A1 and A2, a path through which moisture
penetrates to the region in which A1 and A2 and the band portions
B1 and B2 meet may be blocked to thereby improve moisture
resistance reliability.
[0121] However, the present disclosure is not limited thereto, and
the conductive resin layers 131b' and 132b' may not be disposed on
the electrode layers 131a' and 132a' of the connection portions A1
and A2.
[0122] Here, the external electrodes 131' and 132' include plating
layers 131c' and 132c', respectively, and at least a portion of the
plating layers 131c' and 132c' may be in direct contact with the
electrode layers 131a' and 132a' at the connection portions A1 and
A2, respectively, and the plating layers 131c' and 132c' may be in
direct contact with the conductive resin layers 131b' and 132b' at
the band portions B1 and B2, respectively.
[0123] Referring to FIG. 8, since the conductive resin layers 131b'
and 132b' are not disposed at a partial region of the connection
portions A1 and A2, respectively, the plating layers 131c' and
132c' and the electrode layers 131a' may be in direct contact with
each other at the connection portions 131c' and 132c'.
[0124] Meanwhile, it may be difficult to completely remove the
paste for the conductive resin layer applied to the connection
portions A1 and A2. Thus, according to another exemplary embodiment
in the present disclosure, the conductive resin layers 131b'' and
132b'' may be discontinuously disposed at the connection portions
A1 and A2 of the external electrodes 131'' and 132''.
[0125] Referring to FIG. 9, the residual paste for the conductive
resin layers of the connection portions A1 and A2 may be cured so
that the conductive resin layers 131b'' and 132b'' may be arranged
as a plurality of islands r at the connection portions A1 and
A2.
[0126] Accordingly, a region in which the electrode layers 131a''
and 132a'' and the plating layers 131c'' and 132c'' are in contact
with each other may also be discontinuous at the connection
portions A1 and A2.
[0127] As set forth above, according to an exemplary embodiment,
the flexural strength characteristics may be improved as the
conductive resin layer includes both the epoxy resin and the
acrylic resin.
[0128] In addition, according to an exemplary embodiment, the ESR
may be lowered by reducing the average thickness of the conductive
resin layer at the connection portion compared to that at the band
portion.
[0129] However, the various and beneficial advantages and effects
of the present disclosure are not limited to the aforementioned
contents and may be more easily understood in the course of
describing specific exemplary embodiments of the present
disclosure.
[0130] While example exemplary embodiments have been shown and
described above, it will be apparent to those skilled in the art
that modifications and variations could be made without departing
from the scope of the present disclosure as defined by the appended
claims.
* * * * *